Waspish Multitaskers

It turns out some wasps may be better at scheduling than most humans.  

New research showed that female digger wasps, Ammophila pubescens, can remember the locations of up to nine separate nests and feed their offspring in precise order by age, adjusting their routine depending on need and even tragedy. 

“Our findings suggest that the miniature brain of an insect is capable of remarkably sophisticated scheduling decisions,” the lead author of a new study, Jeremy Field of the University of Exeter, explained in a statement. “In fact, they can remember where and when they have fed their young, and what they fed them, in a way that would be taxing even to human brains.” 

To arrive at this conclusion, scientists observed wild wasps in the sandy heathlands of Surrey, in southeastern England.  

They saw how each female dug multiple short burrows in bare ground, each home to a single egg laid atop a paralyzed caterpillar. Over the following days, the mother returned to each burrow to drop off more caterpillar snacks – sometimes up to eight – before sealing the nest for good. 

The study found that wasp mothers almost always delivered food to their offspring in strict age order – feeding the eldest first 81 percent of the time, according to Cosmos Magazine.  

If an egg died, the mother laid a replacement egg and pushed that nest to the end of the feeding line. But when researchers swapped out caterpillars to give some nests larger initial meals, mothers waited longer before returning – suggesting they adjust care based on prior investment. 

That is even more impressive, Fields noted, because the mothers had an almost eidetic memory about finding their nest and rarely mixed it up with hundreds of identical ones. 

“Only 1.5 percent of the 1,293 food deliveries in the study went to other females’ nests,” he explained. 

While scientists still don’t know how the insects manage these cognitive feats with such tiny brains, the findings add to a body of evidence about the complexity of wasp brains. 

In 2020, researchers at Cornell University discovered that one species of paper wasps can recognize individual faces among their peers. 

“Lots of experiments have been done in labs… But this study shows what the wasps really do in the wild,” Field said. “It reveals why this ability is relevant to their lives, and why natural selection has favored this.”